Concrete Patio Settling Fix

Is there a concrete patio settling fix that can be done? I have a large raised stamped concrete patio (about 30 feet by 35 feet. It is divided into 8 sections for expansion concerns.

My problem is that one side has settled about 3 inches. Is there some way to force a substance underneath the concrete to raise and stabilize the surface?

ANSWER

I can only give you a guess at this since I am not a mason. If you go to my page Building a Patio you will see how a concrete patio (stamped or regular) should be built and you will see the layers.

This is shown in the last image on the page.You will see (from the bottom up) that there is undisturbed soil at the bottom, followed by compacted aggregate. The top layer is a 4 to 8 inch concrete slab.

In order to consider repairing your area that has settled, it's helpful to look at why this could have happened. The most logical cause is that the soil at the bottom was not virgin soil and might have been fill. It is also possible that the soil is very sandy.

It might be possible to get beneath the concrete with a machine and adjust the soil. If it was fill, it would be difficult to rework the soil (tamping it in 12" lifts is the acceptable solution) and get in there beneath the existing concrete slab.

Replacing it with aggregate is another solution that seems more feasible.

This would have to be done carefully since as you work beneath the concrete the concrete has no support and could crack. Can it be supported by another means while working beneath it? Possibly...I don't know the mechanics of this. Houses are supported this way, but a concrete slab is more delicate.

These are my thoughts. Although I haven't given you a specific yes or no answer, at least you have some information if you decide to contact a contractor.

If you are ever entertaining the thoughts of replacing it, please see my page on Paving Costs.

"Susan, what a pleasure it was to work with you. You made me feel like I was your only client - responding late at night and always so quickly! Your design is amazing and we only hope we can do justice to it when we plant. You have such fantastic ideas and you are so open to suggestions and changes. Loved working with you - now if you could only come to Canada and plant it!!!"Helen, Ontario-Canada